They're either entirely incompetent or they're intentionally driving away 3rd party apps. I can't see any other alternative than that.
NSFW on Reddit isn't just porn, the tag is used in the literal sense of "your boss wouldn't approve" or as a content warning for violence, heavy subjects, etc.
e.g. https://old.reddit.com/r/AskReddit/search?q=nsfw%3Ayes&restr...
Reddit's leadership had the potential headline "3rd party developer claims tiff with reddit administration in post" and took it upon themselves to upgrade it to what's here.
There's a reason everyone pushes you to install their app; they want all that sweet, sweet time/network/location data and the ability to drive traffic to whatever degree they want via notifications.
I believe notifications also allow them to wake their app and collect data at that point in time, which they couldn't ordinarily do because iOS and Android have much more restrictions on background activity?
This doesn't seem to make sense. If Reddit wanted to kill 3rd party apps, they would just disable public API access entirely. The reaction would be basically the same it seems.